DESCRIPTION: This application requests partial support of the Keystone Symposium on Cell and Molecular Biology of Dendritic Cells. Specialized dendritic cells (DC) are important antigen presenting cells during the generation of immunity and tolerance. The molecular and cellular mechanisms of dendritic cell function are now more accessible, primarily because of methods to generate dendritic cells in larger numbers and in different functional states. The conference will address several emerging new areas of dendritic cell biology, and interface these areas with B and T lymphocyte functions, particularly in situ in lymphoid organs. Topics will include (1) evidence for distinct myeloid and lymphoid pathways of DC development, (2) the key role of the TNF-receptor family in the control of DC function, (3) molecular genetic approaches to DC biology and DC-restricted products, (4) antigen processing pathways, (5) chemokine production and chemokine receptors, (6) communications between DCs and T cells, and between different types of DCs and B cells, (7) the interactions of viruses with DCs, (8) DCs and the control of Th1/Th2 differentiation, (9) DCs at mucosal surfaces, and (10) DCs in central and peripheral tolerance. To properly interface DCs with lymphocyte function, several of the invited speakers will be experts in emerging areas of immunobiology. The conference organizers are Ralph Steinman, Professor in the Laboratory of Cellular Physiology and Immunology at Rockefeller University; Michel Nussenzweig, Professor in the Laboratory of Molecular Immunology at Rockefeller University; and Jacques Banchereau, Director of the Baylor Institute for Immunology Research.